STMicroelectronics, 32 bit ARM Cortex M0+, STM32L031C4 Microcontroller, 32 MHz, 16kB FLASH, 48-Pin LQFP

1.65 V to 3.6 V power supply

-40 to 125 °C temperature range

0.25 μA Standby mode (2 wakeup pins)

0.38 μA Stop mode (16 wakeup lines)

0.68 μA Stop mode + RTC + 8 KB RAM retention

Down to 76 μA/MHz in Run mode

5 μs wakeup time (from Flash memory)

41 μA 12-bit ADC conversion (at 10ksps)

Core: ARM® 32-bit Cortex®-M0+

From 32 kHz up to 32 MHz max.

0.95 DMIPS/MHz

Ultra-safe, low-power BOR (brownout reset) with 5 selectable thresholds

Ultralow power POR/PDR

Programmable voltage detector (PVD)

Clock sources

1 to 25 MHz crystal oscillator

32 kHz oscillator for RTC with calibration

High speed internal 16 MHz factory-trimmed RC (+/- 1%)

Internal low-power 37 kHz RC

Internal multispeed low-power 65 kHz to 4.2 MHz RC

PLL for CPU clock

Pre-programmed bootloader

USART, SPI supported

Development support

Serial wire debug supported

Up to 38 fast I/Os (31 I/Os 5V tolerant)

Memories

Up to 32 KB Flash with ECC

8 KB RAM

1 KB of data EEPROM with ECC

20-byte backup register

Sector protection against R/W operation

Rich Analogue peripherals

12-bit ADC 1.14 Msps up to 10 channels (down to 1.65 V)

2x ultra-low-power comparators (window mode and wake up capability, down to 1.8 V)

7-channel DMA controller, supporting ADC, SPI, I2C, USART, Timers

5x peripherals communication interface

1x USART (IrDA), 1x UART (low power)

1x SPI 16 Mbits/s

1x I2C (SMBus/PMBus)

8x timers: 1x 16-bit with up to 4 channels, 2x 16-bit with up to 2 channels, 1x 16-bit ultra-low-power timer, 1x SysTick, 1x RTC and 2x watchdogs (independent/window)

CRC calculation unit, 96-bit unique ID